std::variant::swap

void swap(variant& rhs)

Swaps two variant objects.

• if both *this and rhs are valueless by exception, does nothing
• otherwise, if both *this and rhs hold the same alternative, calls swap(std::get<i>(*this), std:get<i>(rhs)) where i is index(). If an exception is thrown, the state of the values depends on the exception safety of the swap function called.
• otherwise, exchanges values of rhs and *this. If an exception is thrown, the state of *this and rhs depends on exception safety of variant's move constructor and move assignment operators.

This overload only participates in overload resolution if std::is_swappable_v<T_i> is true for all T_i in Types...

Parameters

Return value

(none).

Exceptions

May throw any exception thrown by swap(get<i>(*this), get<i>(rhs)) with i being index() and variant's move constructor and move assignment operator.

Example